3.13. Аргументтің қандай мәнінде функцияның мәні 4-ке тең? 1) \(f(x)=\frac6{x-2}\); 2) \(f(x)=\frac{x+1}{x-3}\); 3) \(f(x)=\frac3x+3\); 4) \(f(x)=\frac{x}{x-2}+5\).

1. \[\frac6{x-2}=4\Rightarrow 6=4x-8\Rightarrow x=\frac72.\]

2. \[\frac{x+1}{x-3}=4\Rightarrow x+1=4x-12\Rightarrow 13=3x\Rightarrow x=\frac{13}{3}.\]

3. \[\frac3x+3=4\Rightarrow \frac3x=1\Rightarrow x=3.\]

4. \[\frac{x}{x-2}+5=4\Rightarrow \frac{x}{x-2}=-1\Rightarrow x=-(x-2)\Rightarrow 2x=2\Rightarrow x=1.\]

Жауап: 1) \(x=\frac72\); 2) \(x=\frac{13}{3}\); 3) \(x=3\); 4) \(x=1\).